<?php
class Transaction extends AppModel {

	var $belongsTo = array(
		'Account',
		'Ledger',
	);

	var $hasMany = array(
		'LedgerEntry',
		'StatementEntry',

		'Charge' => array(
			'className' => 'StatementEntry',
			'conditions' => array('Charge.type' => 'CHARGE')
		),

		'Payment' => array(
			'className' => 'StatementEntry',
			'conditions' => array('Payment.type' => 'PAYMENT')
		),

		'Debit' => array(
			'className' => 'LedgerEntry',
			'conditions' => array('Debit.crdr' => 'DEBIT')
		),

		'Credit' => array(
			'className' => 'LedgerEntry',
			'conditions' => array('Credit.crdr' => 'CREDIT')
		),

	);


  /**************************************************************************
   **************************************************************************
   **************************************************************************
   * function: addInvoice
   *  - Adds a new invoice invoice
   */

  function addInvoice($data, $customer_id, $lease_id = null) {
    // Establish the transaction as an invoice
    $invoice =& $data['Transaction'];
    $invoice['type'] = 'INVOICE';
    $invoice['crdr'] = 'DEBIT';
    $invoice['account_id'] = $this->Account->accountReceivableAccountID();

    // Go through the statement entries and flag as charges
    foreach ($data['Entry'] AS &$entry) {
      $entry['type'] = 'CHARGE';
      $entry['crdr'] = 'CREDIT';
    }

    $ids = $this->addTransaction($data, $customer_id, $lease_id);
    if (isset($ids['transaction_id']))
      $ids['invoice_id'] = $ids['transaction_id'];

    return $ids;
  }


  /**************************************************************************
   **************************************************************************
   **************************************************************************
   * function: addReceipt
   *  - Adds a new receipt
   */

  function addReceipt($data, $customer_id, $lease_id = null) {
    // Establish the transaction as an receipt
    $receipt =& $data['Transaction'];
    $receipt['type'] = 'RECEIPT';
    $receipt['crdr'] = 'CREDIT';
    $receipt['account_id'] = $this->Account->accountReceivableAccountID();

    // Go through the statement entries and flag as payments
    foreach ($data['Entry'] AS &$entry) {
      $entry['type'] = 'PAYMENT';
      $entry['crdr'] = 'DEBIT';
      if (isset($entry['Tender']['tender_type_id'])) {
	$entry['account_id'] = $this->LedgerEntry->Tender->TenderType->
	  accountID($entry['Tender']['tender_type_id']);
      }
    }

    $ids = $this->addTransaction($data, $customer_id, $lease_id);
    if (isset($ids['transaction_id']))
      $ids['receipt_id'] = $ids['transaction_id'];

    return $ids;
  }


  /**************************************************************************
   **************************************************************************
   **************************************************************************
   * function: verifyTransaction
   *  - Verifies consistenty of new transaction data
   *    (not in a pre-existing transaction)
   */
  function verifyTransaction($transaction, $entries) {
    pr(array("Transaction::verifyTransaction()"
	     => compact('transaction', 'entries', 'customer_id', 'lease_id')));

    // Verify required Transaction data is present
    if (empty($transaction['type']) ||
	empty($transaction['account_id']) ||
	empty($transaction['crdr']) ||
	(in_array($transaction['type'], array('INVOICE', 'RECEIPT'))
	 && empty($transaction['customer_id'])) ||
	(in_array($transaction['type'], array('INVOICE'))
	 && empty($transaction['lease_id']))
	) {
      pr(array("Transaction::verifyTransaction()"
	       => "Transaction verification failed"));
      return false;
    }

    // Verify all entries
    foreach ($entries AS $entry) {
      extract($entry);
      if (!$this->LedgerEntry->DoubleEntry->verifyDoubleEntry($le1, $le2, $le1_tender)) {
	pr(array("Transaction::verifyTransaction()"
		 => "Double Entry verification failed"));
	return false;
      }
      if (!$this->StatementEntry->verifyStatementEntry($se)) {
	pr(array("Transaction::verifyTransaction()"
		 => "Statement Entry verification failed"));
	return false;
      }
    }

    return true;
  }


  /**************************************************************************
   **************************************************************************
   **************************************************************************
   * function: addTransaction
   *  - Adds a new transaction, and the appropriate ledger and statement
   *    entries, as layed out in the $data['Entry'] array.  The array is
   *    overloaded, since it is used to create both ledger _and_ statement
   *    entries.
   *
   * $data
   *   - Transaction
   *     - [MANDATORY]
   *       - type (INVOICE, RECEIPT)
   *       - account_id
   *       - crdr
   *     - [OPTIONAL]
   *       - stamp
   *         (default: NOW)
   *       - comment
   *     - [AUTOMATICALLY SET] (if set, these items will be overwritten)
   *       - id
   *       - amount
   *       - customer_id
   *       - ledger_id
   *
   *   - Entry (array)
   *     - [MANDATORY]
   *       - type (CHARGE, PAYMENT)
   *       - account_id
   *       - crdr
   *       - amount
   *     - [OPTIONAL]
   *       - effective_date
   *       - through_date
   *       - due_date
   *       - comment (used for statement or ledger entry, based on context)
   *       - ledger_entry_comment
   *       - statement_entry_comment
   *       - Tender
   *         - [MANDATORY]
   *           - tender_type_id
   *         - [OPTIONAL]
   *           - name
   *             (default: Entry Account Name & data1)
   *           - data1, data2, data3, data4
   *           - comment
   *         - [AUTOMATICALLY SET] (if set, these items will be overwritten)
   *           - id
   *           - ledger_entry_id
   *           - deposit_transaction_id
   *           - nsf_transaction_id
   *     - [AUTOMATICALLY SET] (if set, these items will be overwritten)
   *       - id
   *       - transaction_id
   *       - ledger_id
   *
   */

  function addTransaction($data, $customer_id, $lease_id = null) {
    pr(array("Transaction::addTransaction()"
	     => compact('data', 'customer_id', 'lease_id')));

    if (!isset($data['Transaction']) || !isset($data['Entry']))
      return array('error' => true);

    // Automatically figure out the customer if we have the lease
    if (!empty($lease_id) && empty($customer_id)) {
      $L = new Lease();
      $L->recursive = -1;
      $lease = $L->read(null, $lease_id);
      $customer_id = $lease['Lease']['customer_id'];
    }

    // Set the customer based on caller request, and set
    // ledger ID as the current ledger of the specified account
    $transaction = $data['Transaction'];
    $transaction['customer_id'] = $customer_id;
    $transaction['lease_id'] = $lease_id;
    $transaction['ledger_id'] =  
      $this->Account->currentLedgerID($transaction['account_id']);


    // Break each entry out of the combined statement/ledger entry
    // and into individual entries appropriate for saving.  While
    // we're at it, calculate the transaction total as well.
    $transaction['amount'] = 0;
    foreach ($data['Entry'] AS &$entry) {
      // Add entry amount into the transaction total
      $transaction['amount'] += $entry['amount'];

      $entry['customer_id'] = $transaction['customer_id'];
      $entry['lease_id'] = $transaction['lease_id'];
      $entry['ledger_id'] = 
	$this->Account->currentLedgerID($entry['account_id']);

      // Set up our comments, possibly using the default 'comment' field
      if (empty($entry['ledger_entry_comment'])) {
	if (!empty($entry['comment']) && $entry['type'] === 'PAYMENT')
	  $entry['ledger_entry_comment'] = $entry['comment'];
	else
	  $entry['ledger_entry_comment'] = null;
      }
      if (empty($entry['statement_entry_comment'])) {
	if (!empty($entry['comment']) && $entry['type'] === 'CHARGE')
	  $entry['statement_entry_comment'] = $entry['comment'];
	else
	  $entry['statement_entry_comment'] = null;
      }

      // Create one half of the Double Ledger Entry (and the Tender)
      $le1 =
	array_intersect_key($entry,
			    array_flip(array('account_id', 'crdr', 'amount')));
      $le1['comment'] = $entry['ledger_entry_comment'];
      $le1_tender = isset($entry['Tender']) ? $entry['Tender'] : null;

      // Create the second half of the Double Ledger Entry
      $le2 =
	array_intersect_key($transaction,
			    array_flip(array('account_id', 'crdr'))) +
	array_intersect_key($entry,
			    array_flip(array('amount')));

      // Create a statement entry
      $se =
	array_intersect_key($transaction,
			    array_flip(array('customer_id', 'lease_id'))) +
	array_intersect_key($entry,
			    array_flip(array('type', 'account_id', 'amount',
					     'effective_date', 'through_date', 'due_date')));
      $se['comment'] = $entry['statement_entry_comment'];

      // Replace combined entry with our new individual entries
      $entry = compact('le1', 'le1_tender', 'le2', 'se');
    }

    // Move forward, verifying and saving everything.
    $ret = array();
    if (!$this->verifyTransaction($transaction, $data['Entry'], $customer_id, $lease_id))
      return array('error' => true) + $ret;

    pr(array('Transaction::addTransaction' =>
	     array('checkpoint' => 'Pre Transaction Save')
	     + compact('transaction')));

    // Save transaction to the database
    $this->create();
    if (!$this->save($transaction))
      return array('error' => true) + $ret;

    // Set up our return ids array
    $ret['transaction_id'] = $this->id;
    $ret['entries'] = array();
    $ret['error'] = false;

    // Go through the entered charges
    foreach ($data['Entry'] AS $e_index => &$entry) {
      extract($entry);
      $le1['transaction_id'] = $ret['transaction_id'];
      $le2['transaction_id'] = $ret['transaction_id'];
      $se['transaction_id']  = $ret['transaction_id'];

      $result = $this->LedgerEntry->DoubleEntry->addDoubleEntry($le1, $le2, $le1_tender);
      $ret['entries'][$e_index]['DoubleEntry'] = $result;
      if ($result['error']) {
	$ret['error'] = true;
	continue;
      }

      if ($se['type'] === 'CHARGE') {
	// CHARGES need to be added as statement entries.
	// PAYMENTS will be added later after reconciliation
	$result = $this->StatementEntry->addStatementEntry($se);
	$ret['entries'][$e_index]['StatementEntry'] = $result;
	if ($result['error']) {
	  $ret['error'] = true;
	  continue;
	}
      }
    }

    // REVISIT <AP>: 20090723
    //  Now that we have new entries, WE MUST RECONCILE
    //  THE CHARGES TO CUSTOMER ACCOUNT BALANCE!  This
    //  is the only way "payments" are generated, and
    //  the only way to make use of a positive customer
    //  balance if new charges have been entered.

    if (!$ret['error']) {
      $result = $this->StatementEntry->assignCredits
	(array('link' => array('Customer'),
	       'conditions' => array('Customer.id' => $customer_id)),
	 ($transaction['type'] === 'RECEIPT'
	  ? $ret['transaction_id']
	  : null));

      $ret['assigned'] = $result;
      if ($result['error'])
	$ret['error'] = true;
    }

    pr(array('Transaction::addTransaction' =>
	     array('return' => $ret)));

    return $ret;
  }


  /**************************************************************************
   **************************************************************************
   **************************************************************************
   * function: stats
   *  - Returns summary data from the requested transaction
   */
  function stats($id = null, $query = null, $balance_account_id = null) {
    //pr(array('Transaction::stats' => compact('id', 'query')));

    $this->queryInit($query);
    unset($query['group']);

    if (isset($id)) {
      $query['conditions'][] = array('Transaction.id' => $id);
      $query['group'] = 'Transaction.id';
    }
    else
      // CakePHP seems to automagically add in our ID as a part
      // of the query conditions, but only on a 'first' query,
      // not an 'all'.  I suppose this is helpful :-/
      unset($this->id);

    if (empty($query['fields']))
      $query['fields'] = array();

    $stats = array();
    foreach (array_keys($this->hasMany) AS $table) {
      $squery = $query;
      $squery['link'][$table] = array('fields' => array());

      if ($table == 'LedgerEntry') {
	if (isset($balance_account_id)) {
	  $squery['link']['LedgerEntry']['Account'] = array('fields' => array());
	  $squery['conditions'][] = array("Account.id" => $balance_account_id);
	}

	$squery['fields'] = array_merge($squery['fields'],
					$this->LedgerEntry->debitCreditFields(true, $balance_account_id != null));
      }
      elseif ($table == 'StatementEntry') {
	$squery['fields'] = array_merge($squery['fields'],
					$this->StatementEntry->chargePaymentFields(true));
      }
      else {
	$squery['fields'][] = "SUM({$table}.amount) AS total";
	$squery['fields'][] = "COUNT({$table}.id) AS entries";
      }
      $stats[$table] = $this->find('first', $squery);
      // REVISIT <AP>: 20090724
      //   [0][0] is for when we do an 'all' query.  This can
      //   be removed at some point, but I'm keeping it while
      //   toggling between 'all' and 'first' (testing).
      if (isset($stats[$table][0][0]))
	$stats[$table] += $stats[$table][0][0];
      else
	$stats[$table] += $stats[$table][0];
      unset($stats[$table][0]);
    }

    //pr(array('Transaction::stats' => array('return' => compact('stats'))));
    return $stats;
  }
}
?>